Many studies have addressed whether delinquent behavior is associated with various aspects of schooling and academics. However, this research has been limited to examining unidirectional effects. Building on Thornberry's interactional theory, we develop a conceptual model that posits reciprocal associations among delinquent behavior, school attachment, and academic achievement. The model is tested with two waves from the Add Health data set (n = 9,381) that include measures of transcript grade point average (GPA). The results of a set of structural equation models provide evidence that academic achievement is associated with less delinquent behavior over time, as well as with higher school attachment. However, the effects of delinquency are limited to an attenuating effect on subsequent school attachment; delinquency does not directly influence academic achievement. Thus, we find only partial support for interactional theory.